If they didn't have anuses then they would all just gradually expand with poo until, in a few episodes' time, they exploded in a literal shitstorm. And you really don't want to see that in a cartoon series.
Well if it's realism you want how come Georgina is out half the night with a load of talking animals who most likely aren't even CRB'd? And health and saftey'd be appalled at her method of exiting the bedroom via that giraffe's neck.
Well if they have to have anuses in the name of realism, why stop there? Do you people expect all your cartoon characters to have cock n balls too, cause I didn't see any of those. And no, it doesn't really bother me, what a strange surmise. I just thought it odd, that's all. I do not have a bum hole. I am like an old fashioned doll with built in knickers.